The reductive amination of 1,3-cyclohexanedicarboxaldehyde or 1,3-cyanocyclohexanecarboxaldehyde produces a side product known as bicyclic amine or BA (3-azabicyclo[3.3.1]nonane). The formation of bicyclic amine contributes to lower yield of the desired 1,3-bis(aminomethyl)cyclohexane. Currently, there are not any meaningful means of conversion of such by-products to desired diamine products. Accordingly, there is a need for a process for the conversion of aliphatic cyclic amines to aliphatic diamines.